Num 11:24 So Moses went out and told the people the words of Yahveh. And he gathered seventy men of the elders of the people and positioned them around the tent.
Num 11:25 Then Yahveh came down in the cloud and spoke to him, and took some of the Spirit that was on him and put it on the seventy elders. And as soon as the Spirit rested on them, they prophesied. But they did not continue doing it.
Num 11:26 Now two men remained in the camp, one named Eldad, and the other named Medad, and the Spirit rested on them. They were among those registered, but they had not gone out to the tent, and so they prophesied in the camp.
Num 11:27 And a young man ran and told Moses, “Eldad and Medad are prophesying in the camp.”
Num 11:28 And Joshua the son of Nun, the assistant of Moses from his youth, said, “My master Moses, stop them.”
Num 11:29 But Moses said to him, “Are you jealous for my sake? I wish that all Yahveh’s people were prophets, that Yahveh would put his Spirit on them!”
Num 11:30 And Moses and the elders of Israel returned to the camp.

this strange thing

Joshua just couldn’t understand what Eldad and Medad were doing. His theology told him that only Moses could do that. His history reminded him of what had happened when Nadab and Abihu dared to do something different. So, he rushed to get Moses to intervene. Moses had no desire to intervene in this strange thing, because it was the Holy Spirit doing it.

Since Pentecost, the Holy Spirit is doing a strange thing too. He is being poured out on our sons and daughters, our old, our young — all his servants.

LORD, give us the wisdom of Moses, not to try to oppose what your Holy Spirit is doing in our generation.